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    <title>Document</title>
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    <script>
      var num1 = +prompt('请输入第一个数：')
      var num2 = +prompt('请输入第二个数：')
      var num3 = +prompt('请输入第三个数：')
      var res = num1 > num2 ? (num1 > num3 ? num1 : num3) : num2 > num3 ? num2 : num3
      alert(res)
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